overlearn

verb

1. To learn (something) more than is necessary; to study excessively, to take (something) too much to heart.

   “Why the rigmarole of a military survey before enacting a measure most Americans already favoured? Maybe he over-learned the lesson of the clobbering Bill Clinton got when he barged into this area right at the start of his presidency.”

2. To learn (something) to the point where responses become instinctive.
3. Mostly when talking about neural networks, to learn a task to the point where responses actually start to degrade. Compare with overfit, in model tuning contexts.